“The assumption that the “lady” is Jean Brown, the stenographer, quickly leads to a contradiction. Her opening remark brings forth a reply from the person with black hair, therefore Brown’s hair cannot be black. It also cannot be brown, for then it would match her name. Therefore it must be white. This leaves brown for the color of Professor Black’s hair and black for Professor White. But a statement by the person with black hair prompts an exclamation from White, so they cannot be the same person.

It is necessary to assume, therefore, that Jean Brown is a man. Professor White’s hair cannot be white (for then it would match his or her name), nor can it be black because he (or she) replies to the black-haired person. Therefore it must be brown. If the lady’s hair isn’t brown, then Professor White is not a lady. Brown is a man, so Professor Black must be a lady. Her hair can’t be black or brown, so she must be a platinum blonde (Commius: ‘i.e. White’)”

The 25 Q7 tank prize went to two people: Wildowl and Aditi Bhattacharya ! Congrats! Also five players also won consolation prizes of 5 Q7 tanks for still getting the puzzle right with the supported logic: Spiri Solon, omegagamer, Acinem, Sergeant88, and rainy sunday.

I would also like to thank those who donated money or tanks to the prize fund! You guys are awesome!
Now, time for a new puzzle and it’s a simple one to get the juices flowing for the next PRIZE EDITION which will be on Day 1995 (which coincides with my RL birthday!). Feel free to offer answers or comment on this article.

The Colliding Missiles

“Two missiles speed directly toward each other, one at 9,000 miles per hour and the other at 21,000 miles per hour. They start 1,317 miles apart. Without using pencil and paper, calculate how far apart they are one minute before they collide.”

The starting distance is irrelevant, but with one traveling at 9k and 21k, they travel towards each other at a total rate of 30k miles/hour. One minute before impact would be 30k miles/60, or 500 miles : )

The distance seperating the missiles is not relevant since the q. assumes there will be at least one minute of flight time.
keep one object stationary and add its velocity to the other = 30,000 mile/hour
convert that velocity to miles/minute = 500 miles/minute
notice that the distance covered will be the same during any given minute including the last minute which yield a distance traveled in the last minute of 500 miles. ???

Yep, like the others said, 500 miles. 30=5*6, 60 minutes in an hour, so 60*x=30000. 30,000/60=500=the number of miles. As a bored calculation it would take a little over 2.6 minutes for them to collide from where they started.

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